Electronics - Analog and Digital Converters - Discussion

Discussion Forum : Analog and Digital Converters - General Questions (Q.No. 2)
2.
A 4-bit R/2R digital-to-analog (DAC) converter has a reference of 5 volts. What is the analog output for the input code 0101.
0.3125 V
3.125 V
0.78125 V
–3.125 V
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
35 comments Page 4 of 4.

Ashu said:   1 decade ago
Vo = 5(0/16+1/8+0/4+1/2).
Vo = 3.125.

Vaishnavi murugan said:   1 decade ago
Formula = [Vref/(2^n)] {msb bit * 2^0 + next bit * 2^1 + next bit * 2^2 + lsb bit * 2^3}.

Where n = no of bit,

Solution:

Vref = 5v;
n = 4;

=> (5/(2^4)) {0*0 + 1*2 + 0*4 + 1*8}

=> (5/16) {0 + 2 + 0 + 8}

=> (0.3125) {10}

=> 3.125.

Answer => 3.125.

GOPAL said:   1 decade ago
@Nirja.

Formula = (Vref/2^N)(dec equivalent of i/p).

N- is number of significant bits (here 3 as msb is 0).

Here 0101 = 101 hence consider 3 bit.

Therefore,
Vo = 5(Vi/8) = 3.12.

Shah said:   1 decade ago
MOST EASY METHOD:

V(0ut) = (Vi/8)*digital input.

Vimal said:   2 decades ago
Here most significant bit '0' then it's value can be 5 (0/2+1/4+0/8+1/16).


Post your comments here:

Your comments will be displayed after verification.